Electric fan



FIG. 1 is a top, front and left side perspective view of the design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a back elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines illustrate portions of the electric fan that form no part of the claimed design. 

CLAIM The ornamental design for an electric fan, as shown and described. 